1. Field of the Invention
This invention is directed to preloaded joint devices for use in connection with vehicles.
2. Description of the Prior Art
Joint devices of many different constructions and uses are well known, such as those devices used in the automotive field. Since this invention has generally been directed extensively to the field of automotive applications, joint devices in this category are illustrated in such patents as U.S. Pat. Nos. 2,054,082 of Sept. 15, 1936, 3,225,420 of Dec. 28, 1965, 3,395,442 of Aug. 6, l968, and 4,283,833 of Aug. 18, 1981. These joint devices have a housing for a ball stud, bearing means in the housing, a closure plate and preload means for exerting a desired load in the joint assembly to keep the ball stud reasonably tight for a reasonable period of time.
One of the constructional characteristics of these early ball joints is the provision of wear take-up means which extended the useful life before the ball stud became so worn as to cause it to become dangerously loose in its housing. The wear take-up means is usually sealed into the housing by spinning a housing lip over a cover plate to hold the plate against a shoulder in the housing. The tolerance buildup of the components will determine the amount of preload when the ball joint is new. Other means to determine the amount of preload was devised by radially compressing a housing lip over the cover plate.
Most all of the early ball joint devices were expensive to make, the preload was, in a lot of cases, uncertain, and special equipment was necessary to complete the spinning of the housing lip over the closure plate. Other prior art of interest include U.S. Pat. Nos. 2,815,894 of Dec. 1O, 1957 and 4,559,692 of Dec. 24, 1985.